Modern digital logic devices are now being built using 0.13 um process or smaller technology. These small process devices operate at extremely low voltages, much lower voltages than have been previously used for most devices. In the near future, operation below 1 volt will probably be commonplace. One of the challenges in systems that use these low voltage devices is how to cost effectively interface the main source of energy, such as the 5 volt or 12 volt power supply found in typical systems, to the sub 1 volt devices.
In particular, traditional non-isolated buck DC/DC converters may be too inefficient for converting a 12 volt supply to a 1 volt supply. To regulate an output voltage, traditional buck converters may vary the pulse width of the conduction cycle. To convert 12 volts to 1 volt, the duty cycle of traditional non-isolated buck DC/DC converters may be very small, leading to high conversion losses and low power efficiency.